1. Field of the Invention
The present invention relates to a dyeing method of dyeing a plastic lens.
2. Description of Related Art
Conventionally, a dip dyeing method has been adopted in most cases as one of dyeing methods of dyeing plastic lenses for spectacles. This dip dyeing method includes: preparing a dyeing solution by mixing disperse dyes of primary colors of red, blue, and yellow and dispersing the mixture in water; heating the dyeing solution to about 90xc2x0 C.; and dipping a plastic lens into the heated solution, thereby dyeing the lens.
As an alternative to the dip dyeing method, there has been proposed a vapor-deposition dyeing method. This method includes heating sublimatable solid dye under vacuum to sublimate and vapor-deposit the sublimated dye onto a plastic lens which is heated simultaneously under vacuum, thereby dyeing the lens.
The conventional dip dyeing method and vapor-deposition dyeing method, however, has the disadvantages that it is difficult to provide a stably dyed lens. In particular, it is difficult to dye a lens of low dyeability or to dye a lens in deep colors, or in colors of high density. Furthermore, it is desired to more easily and effectively dye a lens.
The present invention has been made in view of the above circumstances and has an object to overcome the above problems and to provide a dyeing method capable of easily and effectively dyeing a plastic lens and also stably dyeing various lenses in various colors.
Additional objects and advantages of the invention will be set forth in part in the description which follows and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
To achieve the purpose of the invention, there is provided a dyeing method of dyeing a plastic lens, including: a step of placing the lens in a predetermined position in a vacuum vapor-deposition device; a step of placing a base body to be used for a dyeing operation in the vapor-deposition device, the base body being applied with dyeing solutions each containing a dissolved or fine-grained dispersed sublimatable dye to form a dye application area on the base body, and the base body being arranged so that the dye application area faces the lens without contact therewith; a step of heating the base body under vacuum in the vapor-deposition device, thereby sublimating the dye of the dye application area to vapor-deposit the sublimated dye on the lens; and a step of heating the lens on which the dye has been vapor-deposited at changing heating temperatures, thereby fixing the dye on the lens.
According to another aspect of the present invention, there is provided a dyeing method of dyeing a plastic lens, including: a step of adding a dyeing auxiliary agent for enhancing fixation of the dye to the lens; a step of placing the lens to which the dyeing auxiliary agent has been added in a predetermined position in a vacuum vapor-deposition device; a step of placing a base body to be used for a dyeing operation in the vapor-deposition device, the base body being applied with dyeing solutions each containing a dissolved or fine-grained dispersed sublimatable dye to form a dye application area on the base body, and the base body being arranged so that the dye application area faces the lens without contact therewith; a step of heating the base body under vacuum in the vapor-deposition device, thereby sublimating the dye of the dye application area to vapor-deposit the sublimated dye on the lens; and a step of heating the lens on which the dye has been vapor-deposited, thereby fixing the dye on the lens.
According to another aspect of the present invention, there is provided a dyeing method of dyeing a plastic lens, including: a step of placing the lens in a predetermined position in a vacuum vapor-deposition device; a step of placing a base body to be used for a dyeing operation in the vapor-deposition device, the base body being applied with dyeing solutions each containing a dissolved or fine-grained dispersed sublimatable dye to form a dye application area on the base body, and the base body being arranged so that the dye application area faces the lens without contact therewith; a step of heating the base body under vacuum in the vapor-deposition device, thereby sublimating the dye of the dye application area to vapor-deposit the sublimated dye on the lens; and a step of heating the lens on which the dye has been vapor-deposited at a heating temperature in a range of 90xc2x0 C. to 150xc2x0 C., thereby fixing the dye on the lens.